#include<stdio.h>
#include<math.h>
#define NUM 320
int number[NUM];
int main()
{
    int i,j,count=0;
    printf("There are following primes sequences in first row:\n");
    for(j=0,i=3;i<=1993;i+=2)
    if(fflag(i))number[j++]=i;
    for(j--;number[j]>1898;j--){
        for(i=0;number[j]-number[i]>1898;i++);
        if(number[j]-number[i]==1898)
        printf("(%d).%3d,......%d\n",++count,number[i],number[j]);
    }
}

fflag(i)
int i;
{int j;
if(i<=1)return(0);
if(i==2)return(1);
if(!(i%2))return(0);
for(j=3;j<=(int)(sqrt((double)i)+1);j+=2)
if(!(i%j))return(0);
return(1);

}